Of the following, the design that best controls for internal validity threats is the
A) posttest only control group design.
B) pretest-posttest group design.
C) time series design.
D) Solomon four-group design.

Question

Quizplus · Accepted Answer

The Solomon four-group design is the best choice for controlling for internal validity threats because it includes both a pretest and a posttest for all four groups, with two groups receiving the treatment and two groups serving as controls. This design allows for control of maturation and historical threats to internal validity, as well as the testing effect. By comparing the pretest and posttest scores of the treatment and control groups, the Solomon four-group design also allows for assessment of the impact of the treatment while controlling for any pre-existing differences between the groups.

Of the Following, the Design That Best Controls for Internal